Using metal silos in the industry for storing materials such as cement, mortar, plaster, wheat germ, etc., is a common practice. It is very important to know at all times the amount of material in the silo to ensure correct use thereof. There are various techniques for measuring this amount, some of which arc based on weighing the silo by installing load cells that adhere to the legs of the silo, others which are based on measuring the fill level by ultrasound, radar, laser, etc. The present invention relates to the former, i.e., silos in which load cells adhered to their legs are installed for measuring by weight the amount of material in the silo.
Today, when a silo is to be implemented for adding therein a measuring system for the purpose of being able to monitor the amount of material therein, the most common practice is to install load cells by screwing them on and adhering them to their legs, which are usually beams with HEB section, or structural metal tubes. These cells are connected to electronic equipment which in turn is connected to the electric network for powering it and communication cables are also installed from the silo to the control cabin for transmitting the data to a weight monitoring system. Today, the most advanced systems have a central server application which connects the sensors of the plant with the sensors of the headquarters through the Internet, or other telecommunication networks.
In the case of moveable silos which are moved with a truck to the work site, the complexity increases since the operation of transporting and erecting the silo causes strong impacts on the legs of the silo which would misadjust and/or break the load cells that are installed thereon. For this reason, movable silos today do not have cells or other measuring systems installed in the legs.
This type of installations will now be described. The silo (1) has therein the bulk to material the amount of which is to be monitored at all times. When it has more material, its legs (3) are subjected to more tension. This tension is measured by installing load cells (4) on said legs. In fixed silos, cells (4) are usually installed on all the legs or only on some of them. The signals of these cells are pulled together in a summation box (5), and the signal (6) is channeled towards the control cabin (2) from this box. Many times Is there is a to pass the cables through underground conduits (9) to take the cables (10) to the electronic control equipment (11) which performs the weighing and displays it on a viewfinder (12). The silo has a motor with a worm screw (7) and electric connection (8) for extracting the material from the silo.
Today, the load cells are screwed onto and adhered to the web of the beam. To that end, there is a need to make two completely normal precise boreholes of the exact diameter in the web of the beam. These boreholes are usually made with a special tool. Once the cell is completely screwed thereon and the cementing adhesive has hardened, they are connected and channeled to the electrical installation. This installation process is laborious, complex and manual, which in business terms means that it is slow and expensive. Furthermore, it complicates the subsequent maintenance as it complicates the replacement of load cells that may be broken.
As a result, nowadays these installations are usually complex and expensive. Many times it is necessary to channel the cables through underground ditches to take the power supply and the data to the control cabin, where the visualization equipment is usually installed so that they are close to the plant operator. As a result, in reality, very few silos have this equipment and as no measuring system is provided, the plant operator tracks the operating procedures to deduce the amount of material in the silo and to decide when he has to order material to fill the silo. If the plant has more than one silo of the same material, this task of the operator is simpler, as he can order material when one silo is emptied, and while the supply arrives, work with the other silo, but in this case the investment for having and maintaining the installation is higher, and the cost of the inventory is also higher, affecting the circulating capital.